Tag: male fetus

There is growing evidence that women around a lot of endocrine disrupting chemicals at home or in jobs such as cleaners, hairdressers and laboratory workers during pregnancyare more likely to have baby boys with a genital defect called hypospadias (a condition where the opening of the urethra is on the underside of the penis rather than at the tip). From Environmental Health News:

Mothers around a lot of endocrine disrupting chemicals at home or in jobs such as cleaners, hairdressers and laboratory workers during pregnancy are more likely to have baby boys with a genital defect, according to a new study in the south of France.The study adds to mounting evidence that fetal exposure to chemicals that mimic people’s natural hormones may cause hypospadias, a condition where the opening of the urethra is on the underside of the penis rather than at the tip.

French researchers examined more than 600 children in the south of France and found that babies exposed to endocrine disrupting chemicals while their genitals were developing were more likely to suffer from hypospadias. Half the boys had hypospadias and half did not. The risk for those exposed was 68 percent higher than the unexposed boys. The researchers ruled out baby boys with known genetic risks for such defects.

The defect, which can be minor or quite severe depending on how far the opening is from the tip, can lead to problems with urination and, later in life, sexual difficulty....It is one of the most common genital defects in baby boys, and most cases require surgery, often done before they reach two years old. In the United States, an estimated five out of 1,000 boys are born annually with hypospadias, while Europe’s rate is slightly less than two out of 1,000.

The researchers estimated the unborn babies’ exposure by looking at their parents’ jobs and where they lived. Working with hormone disrupting chemicals and living in homes near heavy polluters were both linked to more baby boys having the defect. However, the researchers did say a limit of the study was attempting to estimate fetal exposure to such chemicals.Mothers were most likely to have boys with hypospadias if they worked as a cleaner, hairdresser or beautician.

Some of the endocrine disrupting chemicals linked to the professions involved in the study were bisphenol-A (BPA), phthalates, polychlorinated compounds, alkylphenolic compounds and organic solvents. Most exposures—78 percent—occurred in the window of development when babies’ genitals are forming.... but detergents, pesticides, and cosmetics accounted for 75 percent of the cases,” the authors wrote in the study published in the European Urology journal this month.

Other possible causes of the birth defect include older, obese mothers, and fertility or hormone treatments during pregnancy, according to the U.S. Centers for Disease Control and Prevention.

This wasn’t the first time scientists have found a link between certain chemicals and hypospadias. Mothers in southeast England who were heavily exposed to endocrine disrupting phthalates on the job were about three times as likely to have a baby boy with hypospadias. Phthalates are used in some cosmetics, fragrances, food packaging and PVC plastics.

An analysis of 100 million US medical records reveals that autism and intellectual disability (ID) rates are correlated at the county level with incidence of genital malformations in newborn males, an indicator of possible congenital exposure to harmful environmental factors such as pesticides.

Autism rates -- after adjustment for gender, ethnic, socioeconomic and geopolitical factors -- jump by 283 percent for every one percent increase in frequency of malformations in a county. Intellectual disability rates increase 94 percent. Slight increases in autism and ID rates are also seen in wealthier and more urban counties.

The study, published by scientists from the University of Chicago March 13 in PLOS Computational Biology, confirms the dramatic effect of diagnostic standards. Incidence rates for Autism and ID on a per-person basis decrease by roughly 99 percent in states with stronger regulations on diagnosis of these disorders.

"Autism appears to be strongly correlated with rate of congenital malformations of the genitals in males across the country," said study author Andrey Rzhetsky, PhD, professor of genetic medicine and human genetics at the University of Chicago. "This gives an indicator of environmental load and the effect is surprisingly strong."

Although autism and intellectual disability have genetic components, environmental causes are thought to play a role. To identify potential environmental links, Rzhetsky and his team analyzed an insurance claims dataset that covered nearly one third of the US population. They used congenital malformations of the reproductive system in males as an indicator of parental exposure to toxins.

Male fetuses are particularly sensitive to toxins such as environmental lead, sex hormone analogs, medications and other synthetic molecules. Parental exposure to these toxins is thought explain a large portion of congenital reproductive malformations, such as micropenis, hypospadias (urethra on underside of the penis), undescended testicles and others.

The researchers created a statistical baseline frequency of autism and ID across the country. They then looked at the actual rates of these disorders, county-by-county. Deviations from the baseline are interpreted as resulting from local causes. Factors such as age, ethnicity, socioeconomic groups and geopolitical statuses were analyzed and corrected for.

The team found that every one percent increase in malformations in a county was associated with a 283 percent increase in autism and 94 percent increase in ID in that same county. Almost all areas with higher rates of autism also had higher rates of ID, which the researchers believe corroborates the presence of environmental factors. In addition, they found that male children with autism are almost six times more likely to have congenital genital malformations. Female incidence was linked with increased malformation rates, but weakly so. A county-by-county map of autism and ID incidence above or below the predicted baseline for the entire US is included in the study.

Non-reproductive congenital malformations and viral infections in males were also associated with double digit increases in autism and ID rates. Additionally, income appeared to have a weak effect -- every additional $1,000 of income above county average was correlated with around a three percent increase in autism and ID rates. An increased percentage of urban population in a county also showed a weak increase in rates.